Carton



United States Patent CARTON Charles W. Ingham, Ocean City, N. J.

Application June 2, 1954, Serial No. 433,940 3 Claims. (Cl. 229'14) Tlie present invention relates to sift-proof or liquidtight cartons, and particularly those which are capable of receiving and retaining hygroscopic products and liquids or materials which are initially liquid at the time that they are charged, or powdery materials which tend to sift out.

A purpose of the invention is to produce a flat folded sift-proof or liquid-tight carton having increased strength when erected.

A further purpose is to avoid waste of material packed in sift-proof or liquid-tight cartons by avoiding unavailable recesses and stretching" the end of the internal envelope taut.

A further purpose is to provide a liquid-tight container which automatically erects the internal envelope and forms it into a shape convenient for filling.

A further purpose is to fold diagonal end flaps at one or both ends of the envelope around the sides of side flaps of the carton and thus stretch the envelope taut against the inside of the, side flaps and secure the triangular end flaps of the envelope in the space between the side flaps and the end flaps of the carton.

A further purpose is to fold the envelope initially into two diagonal opposed flutes with the end seal extending down the insides of the flutes from their peaks to a midpoint opposite the bases of the flutes, and locate the peaks at midpositions of a side panel and an end panel of the carton.

Further purposes appear in the specification and in the claims.

In the drawings I have chosen to illustrate one only of the numerous embodiments in whch my invention may appear, selecting the form shown from the standpoints of convenience in illustration, satisfactory operation and clear demonstration of the principles involved.

Figures 1 to 3 are plan views showing stepwise construction of the canton of the invention.

Figure 1 shows the glued blank.

Figure 2 illustrates the envelope folded and sealed at one end and glued to one side panel of the blank.

Figure 3 illustrates the carton with its uppermost side panel and end panel folded over and hinged at the adjoining corner, the uppermost side panel being glued to the envelope.

Figure 4 is a perspective of the finished carton in erected form showing the construction of the end.

Describing in illustration but not in limitation and referring to the drawings.

There is a substantial need, in the chemical, food and petroleum industries, for liquid-tight cartons which will permit the shipment of powders and granular materials which are hygroscopic and also of liquids, pastes and materials which should be charged into the container in liquid or paste form and will solidify, as well as powders which will sift. In many cases it is undesirable to employ bottles or drums because of container storage space required prior to filling, cost of freight, and expense of the container, because of the fragile quality of bottles "ice and because ofth'e necessity of returning drums. It is decidedly preferable in many instances to ship a material which requires a liquid-tight or sift-proof container in a container which can be thrown away after use, and need not be stored, reshipped, cleaned and refilled.

The present invention is designed primarily to produce a liquid-tight or sift-proof container for the chemical, food and other industries, which can be shipped and stored flat, and then erected, filled, closed, shipped to the destination and stored until the material is used, and then thrown away.

One of the difficulties in prior art liquid-tight containers such as Ber'gstein U. S. Patent 2,250,249, granted July 22, 1941 for Container, is relative weakness due to fold lines at the middle of both ends which reduce the crushing strength of the container when erected. A further difiiculty is that in prior art liquid-tight contai'nersthe interior envelope has inclined recesses into which a content of paste or the like will deposit, but from which it is impractical to remove, thus causing waste. Another difficulty in the prior art has been that filling and sealing has often been troublesome, and it has been difiicul-t to discharge the contents.

In accordance with the present invention, it is unnecessary to provide folds in the middle of the ends of the container, so that the strength is increased. Furthermore, the end formation of the envelope is straight and taut, free from bulging recesses into which quantities of the content can be deposited and from which it will be difficult to remove the material.

Furthermore the carton of the invention is easy to fill and easy to discharge. I

The invention is applicable for the transportation and storage of relatively small or relatively large quantities of liquids, slurrie's, pastes, materials which solidify from liquid or paste form, powder, and granular materials which should be protected from moisture or which under certain conditions tend to exude or discharge liquid or to sift out powder, insofar as the content does not attack or dissolve the material of the envelope.

, In accordance with the invention I employ a carton blank 20 which may be of fiber board, or any suitable sheet material preferably corrugated fiber board, divided into side panels 21' and 22 and end panels 23' and 24 separated by corner fold lines 25, 26 and 27. At opposite ends the respective side panels have side flaps 28, 30, 31 and 32 preferably of the type which extend half across the end of the erected carton, and likewise the end panels have end flaps 33, 34, 35 and 36 which likewise are of the type which preferably extend halfway across the extended end.

Itwill of course be understood that in a square carton of the character with which we are here preferably concerned, the designation of particular panels and flaps as side or end is purely arbitrary and used for convenience, but where the carton is rectangular, not square, in cross section this will not be the case.

The side and end flaps are of course separated from one another by cut lines 37 which extend in as far as the panels. The flaps also have flap fold lines 38 across the ends of the panels.

After the blank of Figure l is formed, glue is applied to side panel 21 in a pattern as shown in lines 40 and 41 and glue is applied to side panel 22 in a pattern as shown in lines 42 and 43. The glue application can take the form of bars, spots or solid areas. The glue lines 40 and 42 are relatively short because they correspond with relatively short portions of the fold flutes and the glue lines 41 and 43 are longer as they correspond with longer portions of the fold flutes of the envelope as later explained. The glue should not extend down 3 far enough to hamper the expansion of the envelope at the bottom.

The envelope 45 consists of a flattened or gusseted tube which at thepresent stage is open at the top at 46 in Figure 2 and is heat sealed along a seal line 47 at the bottom. The envelope material may be any of a wide variety, suitable material being sheet polyethylene, polyvinyl chloride, polyvinylidene chloride, rubber, synthetic rubber, or the like. In some cases it will be'sufficient to use wax paper, glassene paper, cellophane or the like, although the elastomers are preferred. The envelope in this form extends in width between the corner fold lines 25 and 27 and is pressed against the glue lines 40 and 41 of side panel 21 so that the open end extends beyond the side and end flaps at the top.

The envelope has a fold at the sealed end which is peculiar and important. In the interior of the end there is a fold line 48 which goes straight across from one side to the other of the envelope, and on opposite sides of the fold line 48 there are two flutes 50 and 51, each of which has a corner or peak 52 which is opposed to the other flute and the peak is positioned at a point corresponding to the middle of the side panel 21 or the end panel 24 as the case may be. The heat seal 47 extends along the inside of each flute from the peak 52 to a midpoint 53 which is in line with the corner 26 and on the transverse fold line 48 between the two flutes.

The glue line 41 extends down on the outside of flute 50 for a short distance beyond the level of the transverse fold line 48, but glue line 40 terminates above the flute.

In the next step between Figures 2 and 3, end panel 23 is folded over on top of the envelope and side panel 22 is folded over on top of the envelope, glue lines 42 and 43 adhering to the envelope, glue line 43 extending along the outside of flute 51, While glue line 42 terminates above the flute.

The glue is now allowed to set so that the side panels are joined to the envelope in diagonally opposite relationship. Also hinge 54 is applied to complete the fourth corner as shown in Figure 3. It will of course be understood that it is immaterial from the standpoint of the present invention whether this corner is completed by a tape hinge 54 or by an extended panel strip, staple or other form of fastening. Also desirably the upper or open end of the envelope is tucked inside the carton at 55.

The product of Figure 3 is a completed carton ready for shipment to the point of filling.

In the completed carton the peaks 52 of the flutes are each opposite the midline of one side panel and the adjoining end panel and the intermediate point 53 is opposite the corners between two cooperating pairs of side and end panels.

When the carton arrives at the point of filling it is opened up by pushing together the diagonal corner fold lines 25 and 27 and thus forcing out fold line 26 and hinge 54, and this automatically opens the interior envelope due to the gluing engagement of the side panels 21 and 22 with the envelope. When the carton is erected to open condition the heat seal at the bottom forms as in Figure 4 with the seal 47 extending across to the middle of the ends. The envelope material is desirably pulled taut, forming triangular flaps 56 at the opposite ends. The side flaps of the carton are then folded over the envelope, meeting at the center of the envelope. Triangular flaps 56 are foldedover the sides. of the side flaps and held in the space between the side flaps and the end flaps when the end flaps are folded down over. The flaps are held by glue, tape or other means.

The formation of the end shown in Figure 4 can be applied to the bottom, thus closing access to pockets inside the triangular flaps 56, preventing deposition of material in inaccessible position. Then the carton can be turned over, filled, and the top heat sealed across from the middle of one end to the middle of the other end and the end closed just as the bottom was closed, as shown in Figure 4. Thus the end wall of the envelope is held taut in the top and bottom. Any other special closure for the top can be used including gathering or twisting or securing with bag ties if desired. Likewise the top can be supplied with any special spout or other construction if desired.

In view of my invention and disclosure variations and modifications to meet individual whim or particular need will doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the process and structure shown, and I therefore, claim all such insofar as they fall within the reasonable spirit and scope of my claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

l. A sift-proof carton in flat folded position comprising opposed side panels, opposed end panels, the respective side panels and end panels being interconnected at the corners, side flaps at the opposite ends of the side panels, and end flaps at the opposite ends of the end panels, in combination with a liquid resistant envelope inside the carton and secured thereto at the opposed side panels, the envelope being sealed at one end and being folded at the sealed end in two opposed diagonal flutes, which respectively have peaks, one adjoining the midline of one side panel and the other adjoining the midline of one side panel.

2. A carton according to claim 1, which has a seal at the sealed end which extends from the peak of one flute across the inside of that flute to the corners between one pair of opposed side and end panels and the other pair of opposed side and end panels and then across the inside of the other flute to the peak of that flute, the carton on erection pulling the envelope open so that the seal extends across from the middle of one wall to the middle of the opposite wall.

3. A carton according to claim 2, in which the carton is square in cross section.

References Cited in the file of this patent UNITED STATES PATENTS 2,493,337 Buttery Jan. 3, 1950 

